

[Federal Register: January 7, 2008 (Volume 73, Number 4)]
[Rules and Regulations]               
[Page 1055-1058]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07ja08-6]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0412; Directorate Identifier 2007-NM-290-AD; 
Amendment 39-15327; AD 90-25-05 R1]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 747-100, 747-100B, 747-
100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 
747-400F, 747SR, and 747SP Series Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule; request for comments.

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SUMMARY: The FAA is revising an existing airworthiness directive (AD) 
that applies to all Boeing Model 747 series airplanes. That AD 
currently requires the implementation of a corrosion prevention and 
control program. We issued that AD to prevent degradation of the 
structural capabilities of the affected airplanes. This new AD 
clarifies the applicability of the existing AD by specifying which 
Boeing Model 747 airplanes are affected by this AD because we have 
determined that certain new variants that have not yet been certified 
will not be subject to the requirements of this AD. This AD results 
from reports of incidents involving corrosion and cracking in transport 
category airplanes, which have jeopardized the airworthiness of the 
affected airplanes. We are issuing this AD to prevent degradation of 
the structural capabilities of all Boeing Model 747-100, 747-100B, 747-
100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 
747-400F, 747SR, and 747SP series airplanes.

DATES: Effective January 22, 2008.
    On December 31, 1990 (55 FR 49268, November 27, 1990), the Director 
of the Federal Register approved the incorporation by reference of 
Boeing Document Number D6-36022, ``Aging Airplane Corrosion Prevention 
and Control Program, Model 747,'' Revision A, dated July 28, 1989.
    We must receive comments on this AD by March 7, 2008.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov.
 Follow the instructions for submitting comments.

     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building, Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building, Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact Boeing 
Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov
; or in person at the Docket Management Facility 

between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this AD, the regulatory evaluation, 
any comments received, and other information. The street address for 
the Docket Office (telephone 800-647-5527) is in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Ivan Li, Aerospace Engineer, Airframe 
Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind

[[Page 1056]]

Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6437; 
fax (425) 917-6590.

SUPPLEMENTARY INFORMATION: 

Discussion

    On November 5, 1990, we issued AD 90-25-05, amendment 39-6790 (55 
FR 49268, November 27, 1990). AD 90-25-05 applies to all Boeing Model 
747 series airplanes. That AD requires the implementation of a 
corrosion prevention and control program. That AD resulted from reports 
of incidents involving corrosion and cracking in transport category 
airplanes, which have jeopardized the airworthiness of the affected 
airplanes. We issued that AD to prevent degradation of the structural 
capabilities of the affected airplanes.

Actions Since Existing AD Was Issued

    Since we issued AD 90-25-05, Boeing has announced the production of 
additional Model 747 variants. Although they have not yet been 
certified, the new variants (Model 747-8 and -8F series airplanes) have 
a certification basis that will alleviate the safety issues addressed 
by AD 90-25-05. All of the inspections required by AD 90-25-05 will be 
included in the Boeing Model 747-8/8F Maintenance Review Board Report 
(MRBR) Document and the corresponding Boeing Model 747-8/8F Maintenance 
Planning Data (MPD) Document.
    Because AD 90-25-05 currently applies to ``all Boeing Model 747 
series airplanes,'' these additional Model 747 variants will be 
required to do the actions mandated by that AD, once they are 
certified. Therefore, we must clarify the applicability to specify only 
the airplanes that are affected by this AD.

FAA's Determination and Requirements of This AD

    The unsafe condition described previously is likely to exist or 
develop on other airplanes of the same type design. For this reason, we 
are issuing this AD to revise AD 90-25-05. This new AD retains the 
requirements of the existing AD. This AD also clarifies the 
applicability of the existing AD.

Change to Existing AD

    Since we issued AD 90-25-05, the AD format has been revised, and 
certain paragraphs have been rearranged. As a result, the corresponding 
paragraph identifiers have changed in this AD, as listed in the 
following table:

                      Revised Paragraph Identifiers
------------------------------------------------------------------------
                                             Corresponding  requirement
        Requirement in  AD 90-25-05              in  AD 90-25-05 R1
------------------------------------------------------------------------
paragraph A...............................  paragraph (f).
paragraph B.1.............................  paragraph (g).
paragraph B.2.............................  paragraph (h).
paragraph B.3.............................  paragraph (i).
paragraph C...............................  paragraph (j).
paragraph D...............................  paragraph (k).
paragraph E...............................  paragraph (l).
paragraph F...............................  paragraph (m).
paragraph G...............................  paragraph (n).
------------------------------------------------------------------------

    We have also changed this AD to include numbers on each of the 
notes in the AD.

Costs of Compliance

    We estimate that this AD affects about 165 airplanes of U.S. 
registry. The requirements of this AD add no additional economic 
burden. The current costs for this AD are repeated for the convenience 
of affected operators, as follows:
    We estimate that the actions required by AD 90-25-05 and retained 
in this AD take about 4,720 work-hours per product. The average labor 
rate is $80 per work-hour. Based on these figures, we estimate the cost 
of this AD to U.S. operators to be $62,304,000 or $377,600 per product.
    The number of work hours, as indicated above, is presented as if 
the accomplishment of the actions required by AD 90-25-05 and retained 
in this AD are to be conducted as ``stand alone'' actions. However, in 
actual practice, these actions for the most part will be accomplished 
coincidentally or in combination with normally scheduled airplane 
inspections and other maintenance program tasks. Therefore, the actual 
number of necessary additional work hours will be minimal in many 
instances. Additionally, any costs associated with special airplane 
scheduling will be minimal.

FAA's Determination of the Effective Date

    No airplane variant that we had previously excluded from the 
applicability of this AD is currently on the U.S. Register. Therefore, 
providing notice and opportunity for public comment is unnecessary 
before this AD is issued, and this AD may be made effective in less 
than 30 days after it is published in the Federal Register.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety, and we did not provide you with notice and an opportunity to 
provide your comments before it becomes effective. However, we invite 
you to send any written data, views, or arguments about this AD. Send 
your comments to an address listed under the ADDRESSES section. Include 
``Docket No. FAA-2008-0412; Directorate Identifier 2007-NM-290-AD'' at 
the beginning of your comments. We specifically invite comments on the 
overall regulatory, economic, environmental, and energy aspects of this 
AD. We will consider all comments received by the closing date and may 
amend this AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov
, including any personal information you provide. We 

will also post a report summarizing each substantive verbal contact we 
receive about this AD.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this AD will not have federalism 
implications under Executive Order 13132. This AD will not have a 
substantial direct effect on the States, on the relationship between 
the national government and the States, or on the distribution of power 
and responsibilities among the various levels of government.
    For the reasons discussed above, I certify that the regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979); and
    3. Will not have a significant economic impact, positive or 
negative, on a substantial number of small entities

[[Page 1057]]

under the criteria of the Regulatory Flexibility Act.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this AD and placed it in the AD docket. See the ADDRESSES 
section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec.  39.13  [Amended]

0
2. The Federal Aviation Administration (FAA) amends Sec.  39.13 by 
removing amendment 39-6790 (55 FR 49268, November 27, 1990), and adding 
the following new airworthiness directive (AD):

90-25-05 R1 Boeing: Amendment 39-15327. Docket No. FAA-2008-0412; 
Directorate Identifier 2007-NM-290-AD.

Effective Date

    (a) This AD becomes effective January 22, 2008.

Affected ADs

    (b) This AD revises AD 90-25-05.

Applicability

    (c) This AD applies to all Boeing Model 747-100, 747-100B, 747-
100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 
747-400F, 747SR, and 747SP series airplanes, certificated in any 
category.

Unsafe Condition

    (d) This AD results from reports of incidents involving 
corrosion and cracking in transport category airplanes, which have 
jeopardized the airworthiness of the affected airplanes. We are 
issuing this AD to prevent degradation of the structural 
capabilities of all Boeing Model 747-100, 747-100B, 747-100B SUD, 
747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 
747SR, and 747SP series airplanes.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

    Note 1: This AD references Boeing Document Number D6-36022, 
``Aging Airplane Corrosion Prevention and Control Program, Model 
747,'' Revision A, dated July 28, 1989, for inspection procedures, 
compliance times, and reporting requirements. In addition, this AD 
specifies inspection and reporting requirements beyond those 
included in the Document. Where there are differences between the AD 
and the Document, the AD prevails.

Requirements of AD 90-25-05

Maintenance Program Revision

    (f) Within one year after December 31, 1990 (the effective date 
of AD 90-25-05), revise the FAA-approved maintenance program to 
include the corrosion control program specified in Boeing Document 
Number D6-36022, ``Aging Airplane Corrosion Prevention and Control 
Program, Model 747,'' Revision A, dated July 28, 1989, (hereinafter 
referred to as ``the Document'').

    Note 2: All structure found corroded or cracked as a result of 
an inspection conducted in accordance with paragraph (f) of this AD 
must be addressed in accordance with FAR Part 43.


    Note 3: Where non-destructive inspection (NDI) methods are 
employed, in accordance with Section 4.1 of the Document, the 
standards and procedures used must be acceptable to the 
Administrator in accordance with FAR 43.13.


    Note 4: Procedures identified in the Document as ``optional'' 
are not required to be accomplished by this AD.

Actions if Corrosion is Found

    (g) If, as a result of any inspection conducted in accordance 
with the program required by paragraph (f) of this AD, Level 3 
corrosion is determined to exist in any area, accomplish paragraph 
(g)(1) or (g)(2) of this AD within 7 days after such determination.
    (1) Submit a report of any findings of Level 3 corrosion to the 
Manager of the Seattle Aircraft Certification Office (ACO), FAA, and 
inspect the affected area on all Boeing Model 747-100, 747-100B, 
747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-
400D, 747-400F, 747SR, and 747SP series airplanes in the operator's 
fleet.
    (2) Submit for approval to the Manager of the Seattle ACO the 
proposal or data in paragraph (g)(2)(i) or (g)(2)(ii) of this AD.
    (i) Proposed adjustments to the schedule for performing the 
tasks in that area on remaining airplanes in the operator's fleet, 
which are adequate to ensure that any other Level 3 corrosion is 
detected in a timely manner, along with substantiating data for 
those adjustments.
    (ii) Data substantiating that the Level 3 corrosion found is an 
isolated occurrence and that no such adjustments are necessary.

    Note 5: Notwithstanding the provision of Section 1.1. of the 
Document that would permit corrosion that otherwise meets the 
definition of Level 3 corrosion (i.e., which is determined to be a 
potentially urgent airworthiness concern requiring expeditious 
action) to be treated as Level 1 if the operator finds that it ``can 
be attributed to an event not typical of the operator's usage of 
other airplanes in the same fleet,'' paragraph (g)(2) of this AD 
requires that data substantiating any such finding be submitted to 
the FAA for approval.


    Note 6: As used throughout this AD, where documents are to be 
submitted to the Manager of the Seattle ACO, the document should be 
submitted directly to the Manager, Seattle ACO, and a copy sent to 
the cognizant FAA Principal Inspector (PI). The PI will then forward 
comments or concurrence to the Seattle ACO. The Seattle ACO will not 
respond to the operator without the PI's comments or concurrence.

    (h) The FAA may impose adjustments other than those proposed, 
upon a finding that such adjustments are necessary to ensure that 
any other Level 3 corrosion is detected in a timely manner.
    (i) Prior to the compliance time specified for the first task 
required in the adjusted schedule approved under paragraph (g) or 
(h) of this AD, revise the FAA-approved maintenance program to 
include those adjustments.

    Note 7: The reporting requirements of paragraphs (g) and (k) of 
this AD do not relieve operators from reporting corrosion as 
required by FAR Section 121.703.

Acceptable Extension to Repeat Inspection Interval

    (j) To accommodate unanticipated scheduling requirements, it is 
acceptable for a repeat inspection interval to be increased by up to 
10% but not to exceed 6 months. The cognizant FAA Principal 
Inspector (PI) must be informed, in writing, of any extension.

    Note 8: Except as provided paragraph (j) of this AD, 
notwithstanding Section 3.1., paragraph 4, of the Document, all 
extensions to any compliance time must be approved by the Manager of 
the Seattle ACO.

Report of Levels 2 and 3 Corrosion

    (k) Report forms for Level 2 corrosion and a follow-up report 
for Level 3 corrosion must be submitted at least quarterly in 
accordance with Section 5.0 of the Document.

Approval for Increasing Existing Corrosion Inspection/Task 
Intervals

    (l) If the repeat inspection or task intervals of an operator's 
existing corrosion inspection program are shorter than the 
corresponding intervals in Section 4.3 of the Document, they may not 
be increased without specific approval of the Manager of the Seattle 
ACO.

Addition of an Airplane to Operations Specifications

    (m) Before any airplane that is subject to this AD can be added 
to an air carrier's operations specifications, a program for the 
accomplishment of tasks required by this AD must be established in 
accordance with paragraphs (m)(1) and (m)(2) of this AD.
    (1) For airplanes that have previously been operated under an 
FAA-approved maintenance program, the initial task on each area to 
be accomplished by the new operator must be accomplished in 
accordance with the previous operator's schedule or with the new 
operator's schedule, whichever would result in the earlier 
accomplishment date for that task. After each task has been 
performed once, each subsequent task must be performed in accordance 
with the new operator's schedule.

[[Page 1058]]

    (2) For airplanes that have not previously been operated under 
an FAA-approved maintenance program, each initial task required by 
this AD must be accomplished either prior to the airplane's being 
added to the air carrier's operations specifications, or in 
accordance with a schedule approved by the Manager, Seattle ACO.

Actions for Corrosion That Exceeds Level 1

    (n) If corrosion is found to exceed Level 1 on any inspection 
after the initial inspection, the corrosion control program for the 
affected area must be reviewed and means implemented to reduce 
corrosion to Level 1 or better.
    (1) Within 60 days after such a finding, if corrective action is 
necessary to reduce future findings of corrosion to Level 1 or 
better, such proposed corrective action must be submitted for 
approval to the Manager, Seattle ACO.
    (2) Within 30 days after the corrective action is approved, 
revise the FAA-approved maintenance program to include the approved 
corrective action.

Alternative Methods of Compliance (AMOCs)

    (o)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, ATTN: Ivan Li, Aerospace Engineer, Airframe Branch, ANM-120S, 
FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., 
Renton, Washington 98057-3356; telephone (425) 917-6437; fax (425) 
917-6590; has the authority to approve AMOCs for this AD, if 
requested using the procedures found in 14 CFR 39.19.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by an 
Authorized Representative for the Boeing Commercial Airplanes 
Delegation Option Authorization Organization who has been authorized 
by the Manager, Seattle ACO, to make those findings. For a repair 
method to be approved, the repair must meet the certification basis 
of the airplane and the approval must specifically refer to this AD.
    (4) AMOCs approved previously in accordance with AD 90-25-05, 
are approved as AMOCs for the corresponding provisions of this AD.

Material Incorporated by Reference

    (p) You must use Boeing Document Number D6-36022, ``Aging 
Airplane Corrosion Prevention and Control Program, Model 747,'' 
Revision A, dated July 28, 1989, to perform the actions that are 
required by this AD, unless the AD specifies otherwise.
    (1) The incorporation by reference of Boeing Document Number D6-
36022, ``Aging Airplane Corrosion Prevention and Control Program, 
Model 747,'' Revision A, dated July 28, 1989, was approved 
previously by the Director of the Federal Register as of December 
31, 1990 (55 FR 49268, November 27, 1990).
    (2) Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for a copy of this service information. You 
may review copies at the FAA, Transport Airplane Directorate, 1601 
Lind Avenue, SW., Renton, Washington 98057-3356; or at the National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, call 202-741-6030, or go to: 
http://www.archives.gov/federal-register/cfr/ibr-locations.html.


    Issued in Renton, Washington, on December 26, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-25616 Filed 1-4-08; 8:45 am]

BILLING CODE 4910-13-P
